CVE-2021-36865

Quiz And Survey Master – Best Quiz, Exam and Survey Plugin for WordPress <= 7.3.4 - Insecure Direct Object Reference

2022-09-29 00:00
Ngo Van Thien

Strategic Overview

Status
Patched in 7.3.5
Affected Plugin
Quiz and Survey Master (QSM) – Quiz Maker & Survey Maker
Affected Version
<= 7.3.4
CVSS
5.4Medium
Weakness type
CWE-639 · Authorization Bypass Through User-Controlled Key
CVE
CVE-2021-36865
View all Quiz and Survey Master (QSM) – Quiz Maker & Survey Maker vulnerabilities

At a glance

CVE-2021-36865 is a medium-severity Authorization Bypass Through User-Controlled Key vulnerability in the Quiz and Survey Master (QSM) WordPress plugin, affecting versions <= 7.3.4. It carries a CVSS score of 5.4 (reachable over the network; low attack complexity). The issue is fixed in version 7.3.5; sites on affected versions should update now. Disclosed September 2022, reported by Ngo Van Thien.

Vulnerability Overview

The Quiz And Survey Master plugin for WordPress is vulnerable to insecure direct object reference in versions up to, and including, 7.3.4. This is due to insufficient validation on the key controlling a quiz's id. This makes it possible for authenticated attackers with author-level capabilities and above to change arbitrary quiz content.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no interaction from a victim user.

CWE-639: Authorization Bypass Through User-Controlled Key

Reaching this weakness in Quiz and Survey Master (QSM) <= 7.3.4 takes a caller who can reach the endpoint. Authorization bypass through a user-controlled key, often called insecure direct object reference, means the application looks up a record by an identifier from the request without checking that the caller owns it.

Changing a number in the request is enough to read or modify other users' records, which on commerce and membership sites means customer data. For Quiz and Survey Master (QSM) the fix is 7.3.5: builds <= 7.3.4 are affected, anything from 7.3.5 onward is not.

Remediation

Update to version 7.3.5, or a newer patched version

How does WordSec protect against this?

Because it turns on account access, WordSec's login security is the relevant layer: role-based two-factor, captcha and brute-force limits raise the cost of getting the account this needs. None of that substitutes for the fix: Quiz and Survey Master (QSM) 7.3.5 closes this, and updating the plugin is the step that ends it.

  • Login Security
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-36865https://www.wordfence.com/threat-intel/vulnerabilities/id/6975e84e-06ab-41b1-ae39-64685a878d15https://nvd.nist.gov/vuln/detail/CVE-2021-36865

Related records

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